Zabbix

<?php

/*

** Copyright (C) 2001-2025 Zabbix SIA

**

** This program is free software: you can redistribute it and/or modify it under the terms of

** the GNU Affero General Public License as published by the Free Software Foundation, version 3.

**

** This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;

** without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

** See the GNU Affero General Public License for more details.

**

** You should have received a copy of the GNU Affero General Public License along with this program.

** If not, see <https://www.gnu.org/licenses/>.

**/

​

/**

 * Zabbix log file helper.

 */

class CLogHelper {

​

    /**

     * Log file offsets (for incremental log read).

     *

     * @var array

     */

    private static $log_offsets = [];

​

    /**

     * Clear contents of log.

     *

     * @param string $path    log file path

     */

    public static function clearLog($path) {

        file_put_contents($path, '');

        self::resetLogOffset($path);

    }

​

    /**

     * Reset log offset.

     *

     * @param string $path    log file path

     */

    public static function resetLogOffset($path) {

        self::$log_offsets[$path] = 0;

    }

​

    /**

     * Read content of the log.

     *

     * @param string  $path          log file path

     * @param boolean $incremental   flag to be used to enable incremental read

     *

     * @return string

     *

     * @throws Exception    on cases when log is not available

     */

    public static function readLog($path, $incremental = false) {

        $offset = ($incremental && array_key_exists($path, self::$log_offsets))

                ? self::$log_offsets[$path] : 0;

​

        if (($content = file_get_contents($path, false, null, $offset)) === false) {

            throw new Exception('Failed to read log "'.$path.'".');

        }